The present invention relates to filter cigarettes having a controllable degree of ventilation.
In the provision of cigarettes having reduced deliveries of tar or total particulate matter (TPM), two measures are commonly adopted, namely the provision of a smoke filter at the mouth end of the cigarette, and means for admitting air into the cigarette whereby the smoke stream is diluted, either within the cigarette itself or in the mouth of the smoker.
U.S. Pat. No. 2,936,763 (Saffir) describes a filter cigarette in which the wrapper is formed with a longitudinally extending region perforated or otherwise weakened along its edge so that sections of the wrapper can be easily torn off to admit air into the cigarette. In all the embodiments the region at least partly overlies the tobacco filler, although in one embodiment one small section may overlap the filter.